After the click on "Folder Explorer" the default folder will be opened, but in the upper right corner, next to the search function, there is a menu called "STORAGES"If you open the menu you can switch between "Default Storage" and "Other Storage 1", which is the SD Card.

Furthermore, I believe if you remove that SD card for whatever reason and reinsert it, or upgrade to larger capacity, all of your track analysis will be lost and CrossDJ provides no way to backup and restore track analysis data in case something goes wrong......